试过，贪心能过。

Code:

#include<bits/stdc++.h>
#define int long long
using namespace std;
int a[1010],dp[1010];
int n; 
signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>a[i];
	}
	int k=2,ans=1;
	for(int i=2;i<=n;i++){
		if(k%2==0){
			if(a[i]>=a[i-1]) continue;
		    else{
		    	k++;
		    	ans++;
			}
		}
		else{
			if(a[i]<=a[i-1]) continue;
		    else{
		    	k++;
		    	ans++;
			}
		}
	}
	cout<<ans;
}